Migratory birds are able to navigate over great distances with remarkable accuracy. The mechanism they use to achieve this feat is thought to involve two distinct steps: locating their position (the 'map') and heading towards the direction determined (the 'compass'). For decades, this map-and-compass concept has shaped our perception of navigation in animals, although the nature of the map remains debated.
View Article and Find Full Text PDFNitrite-oxidizing bacteria (NOB) catalyse the second nitrification step and are the main biological source of nitrate. The most diverse and widespread NOB genus is Nitrospira, which also contains complete ammonia oxidizers (comammox) that oxidize ammonia to nitrate. To date, little is known about the occurrence and biology of comammox and canonical nitrite oxidizing Nitrospira in extremely alkaline environments.
View Article and Find Full Text PDFBackground: Dermatitis linearis is a toxic skin lesion caused by contact with certain beetles of the genus Paederus (Coleoptera: Staphylinidae). Dermatitis linearis outbreaks have been described mainly in tropical and subtropical regions, but so far not in Central Europe, and are considered an emerging public health concern potentially associated with climate change.
Material And Methods: Following diagnosis of dermatitis linearis in a cluster of six adults and one child with reported exposure to beetles with morphological characteristics of Paederus species at a recreational public open-air bath at Lake Neusiedl (Illmitz, Burgenland, Austria), we performed on-site inspection and installed light and pitfall traps.
In Austria, only fragmented information on the occurrence of alien and potentially invasive mosquito species exists. The aim of this study is a nationwide overview on the situation of those mosquitoes in Austria. Using a nationwide uniform protocol for the first time, mosquito eggs were sampled with ovitraps at 45 locations in Austria at weekly intervals from May to October 2020.
View Article and Find Full Text PDFMercury (Hg), as one of the most frequently and globally occurring pollutants, is of major public health concern. Aquatic environments are the key compartment for Hg methylation as well as for its consequent bioaccumulation and biomagnification. This mesocosm study investigated the differences in Hg turnover, Hg distribution and bioaccumulation in two contrasting waterbodies: Panozzalacke (PL), an "average", oligotrophic European freshwater body and Lake Neusiedl (LN), an alkaline, saline, eutrophic, biologically highly productive lake.
View Article and Find Full Text PDFFor studies on magnetic compass orientation and navigation performance in small bird species, controlled experiments with orientation cages inside an electromagnetic coil system are the most prominent methodological paradigm. These are, however, not applicable when studying larger bird species and/or orientation behaviour during free flight. For this, researchers have followed a very different approach, attaching small magnets to birds, with the intention of depriving them of access to meaningful magnetic information.
View Article and Find Full Text PDFDisplacement experiments have demonstrated that experienced migratory birds translocated thousands of kilometers away from their migratory corridor can orient toward and ultimately reach their intended destinations. This implies that they are capable of "true navigation," commonly defined as the ability to return to a known destination after displacement to an unknown location without relying on familiar surroundings, cues that emanate from the destination, or information collected during the outward journey. In birds, true navigation appears to require previous migratory experience (but see Kishkinev et al.
View Article and Find Full Text PDFNitrite-oxidizing bacteria of the genus Nitrospira are key players of the biogeochemical nitrogen cycle. However, little is known about their occurrence and survival strategies in extreme pH environments. Here, we report on the discovery of physiologically versatile, haloalkalitolerant Nitrospira that drive nitrite oxidation at exceptionally high pH.
View Article and Find Full Text PDFCalcium (Ca) is an essential element for almost all living organisms. Here, we examined global variation and controls of freshwater Ca concentrations, using 440 599 water samples from 43 184 inland water sites in 57 countries. We found that the global median Ca concentration was 4.
View Article and Find Full Text PDFInsect migrations are spectacular natural events and resemble a remarkable relocation of biomass between two locations in space. Unlike the well-known migrations of daytime flying butterflies, such as the painted lady () or the monarch butterfly (), much less widely known are the migrations of nocturnal moths. These migrations - typically involving billions of moths from different taxa - have recently attracted considerable scientific attention.
View Article and Find Full Text PDFBackground: Uranotaenia unguiculata Edwards, 1913 is a species of mosquito (Diptera: Culicidae) native to central Europe. Recently a novel lineage of the West Nile virus (WNV-lineage 4c) was identified in pools of adult female Ur. unguiculata.
View Article and Find Full Text PDFCan J Infect Dis Med Microbiol
March 2018
Information on mosquito-borne filarioid helminths in Austria is scarce, but recent discoveries of indicate autochthonous distribution of this parasite in Eastern Austria. In the current xenomonitoring study, more than 48,000 mosquitoes were collected in Eastern Austria between 2013 and 2015, using different sampling techniques and storage conditions, and were analysed in pools with molecular tools for the presence of filarioid helminth DNA. Overall, DNA of , , and two unknown filarioid helminths were documented in twenty mosquito pools within the mitochondrial gene (barcode region).
View Article and Find Full Text PDFTrypanosomatid flagellates have not been studied in Austria in any detail. In this study, specific nested PCR, targeted on the ribosomal small subunit, was used to determine the occurrence and diversity of trypanosomatids in wild-caught mosquitoes sampled across Eastern Austria in the years 2014-2015. We collected a total of 29,975 mosquitoes of 19 species divided in 1680 pools.
View Article and Find Full Text PDFBackground: Insect vectors, namely mosquitoes (Diptera: Culicidae), are compulsory for malaria parasites (Plasmodium spp.) to complete their life cycle. Despite this, little is known about vector competence of different mosquito species for the transmission of avian malaria parasites.
View Article and Find Full Text PDFBackground: Culex pipiens complex taxa differ in behaviour, ecophysiology and epidemiologic importance. Despite their epidemiologic significance, information on genetic diversity, occurrence and seasonal and spatial distribution patterns of the Cx. pipiens complex is still insufficient.
View Article and Find Full Text PDFBotulinum neurotoxin C1 (BoNt C1) and its corresponding gene were detected in seven aquatic habitats covering a range of low (LR) to high risk (HR) avian botulism outbreak areas during a study period of 10 months. Toxin and gene in sediment and avian faecal samples were analysed before (in situ) and after cultivation (in vitro) by a newly adapted ELISA, the common mouse bioassay and by a recently described nested PCR protocol. BoNt C1 gene fragments were detected in 74% and 83% of all investigated sediment samples by in situ PCR and in vitro PCR, respectively, at comparable frequencies in HR and LR areas.
View Article and Find Full Text PDFWild birds are an important nonpoint source of fecal contamination of surface waters, but their contribution to fecal pollution is mostly difficult to estimate. Thus, to evaluate the relation between feces production and input of fecal indicator bacteria (FIB) into aquatic environments by wild waterfowl, we introduced a new holistic approach for evaluating the performance of FIB in six shallow saline habitats. For this, we monitored bird abundance, fecal pellet production, and the abundance of FIB concomitantly with a set of environmental variables over a 9-month period.
View Article and Find Full Text PDFDilute soda lakes are among the world's most productive environments and are usually dominated by dense blooms of cyanobacteria. Up to now, there has been little information available on heterotrophic bacterial abundance, production, and their controlling factors in these ecosystems. In the present study the main environmental factors responsible for the control of the heterotrophic bacterial community in five shallow soda pools in Eastern Austria were investigated during an annual cycle.
View Article and Find Full Text PDFDiel changes in bacterial and cyanobacterial numbers, as well as heterotrophic bacterial production, were examined in two shallow alkaline pools, harbouring dense populations of cyanobacteria (up to 1100 x 109 cells l-1) and bacteria (up to 500 x 109 cells l-1). Together with the recorded bacterial production rates (925 micro gC l-1x h-1), these values are the highest reported for natural aquatic ecosystems. The investigations were performed during a fair-weather situation, and during a rapid change after a long-term fair-weather situation to thunderstorms and heavy rainfall.
View Article and Find Full Text PDFBotulism is one of the most important bird diseases world-wide and is caused by the intoxication with Botulinum-Neurotoxin-C1 (BoNt-C1), which is produced by toxigenic clostridia under appropriate conditions. Avian botulism leads regularly to large losses among the migrating bird populations breeding and resting at the saltwater pools of the Austrian national park Neusiedler See-Seewinkel. Despite of its ethical dubiousness and its high technical expense the mouse-bioassay is still used as the routine standard method for the detection of BoNt-C1.
View Article and Find Full Text PDFLett Appl Microbiol
September 2001
Aims: The relationship between the rate of beta-D-glucuronidase hydrolysis (GLUase-HR) and the E. coli concentration in rivers differing in the extent of faecal pollution was investigated. It was hypothesized that the rate of GLUase-HR is a better surrogate parameter for E.
View Article and Find Full Text PDFA fragment of the human low-density lipoprotein receptor encompassing the seven ligand-binding repeats fused to a C-terminal oligo-His tag was expressed in Sf9 insect cells. The melittin signal sequence encoded in the baculovirus vector led to secretion of the protein into the cell supernatant in a soluble form. The receptor fragment bound its natural ligand beta-migrating very-low-density lipoprotein and human rhinovirus serotype 2 in non-reducing ligand blots.
View Article and Find Full Text PDF